Primary, non-exophytic, optic nerve germ cell tumors

Primary anterior visual pathway germinoma in a 13-year-old boy: A case report

Background

Primary optic nerve and chiasmal germinomas are very rare. These lesions can commonly be mistaken for optic pathway gliomas based on imaging alone. It is radiosensitive and cured in most of the cases.

Case Description

We report a rare case of a 13-year-old boy with primary bilateral optic nerves and chiasmal germinoma who underwent partial surgical resection followed by radiotherapy. Follow-up brain imaging after two months post-radiotherapy showed interval regression of the tumor. Our literature review identified that 12 reported cases of primary anterior visual pathway germinoma had been reported to regress significantly post-radiotherapy alone or with chemotherapy.

Conclusion

Histologic correlation is essential for appropriate treatment, alleviating symptoms, and avoiding irreversible vision loss.

Involvement of the optic pathway and outcome of visual function in patients with neurohypophyseal germ cell tumor

BACKGROUND

Patients with neurohypophyseal germ cell tumors (GCTs) typically present with visual problems. Hence, this study aimed to assess optic pathway involvement based on clinical and radiological findings and to validate the outcome of visual function.

METHODS

A total of 16 patients with newly diagnosed neurohypophyseal GCTs who were treated at the University of Tsukuba Hospital between 2000 and 2020 were included in this study.

RESULTS

The median interval from symptom onset to diagnosis was 173.5 days (range, 33-1588 days). Patients with visual disturbance at diagnosis had a longer time to diagnosis compared with those without. Ophthalmologic abnormalities were frequently observed, with an incidence rate of 69%. Fifty percent of patients exhibited optic pathway involvement detected via magnetic resonance imaging (MRI). Visual impairment was more severe in the patients with optic pathway involvement (p = 0.002). Post-treatment visual impairment was improved but was still significantly severe in patients with optic pathway involvement than in those without involvement (p = 0.010). Visual field deficit more likely remained with an improvement rate of 50%, whereas the improvement rate of visual acuity was 78%. Further, none developed late-onset visual deterioration during the follow-up period.

CONCLUSIONS

Visual disturbance and optic pathway involvement are common in neurohypophyseal GCTs. Visual impairment particularly in patients with optic pathway involvement on MRI is more likely to remain at follow-up, although the outcome of visual function is acceptable in most cases.

Intracranial Pure Germinoma With Optic Nerve Infiltration

A 19-year-old man presented with a 3-year history of episodic headaches, right hemiparesis, and progressive vision loss in both eyes. Initially, extensive laboratory testing was unrevealing. MRI later demonstrated progressive enlargement and enhancement of the left optic nerve poorly correlated with the timing of his clinical manifestations. There was no clinical or radiological response to treatment with corticosteroids, mycophenolate mofetil, or rituximab administered empirically for possible inflammatory processes. Later in the disease course, he developed diabetes insipidus (DI), worsening vision to light perception bilaterally, severe cognitive decline, and spastic quadriparesis. Cerebrospinal fluid (CSF) beta human chorionic gonadotropin (β-hCG) was elevated. Eventually, a left optic nerve biopsy was performed, which was consistent with an intracranial pure germinoma with infiltration of the optic nerve and disseminated leptomeningeal disease. Although rare, intracranial germ cell tumors can primarily involve the anterior visual pathways and should be considered in the setting of DI and elevated CSF β-hCG.

Visual complaints in intracranial germinomas

OBJECTIVE

Patients with brain tumors often report having visual complaints. This may be due to increased intracranial pressure, compression/invasion of the optic pathway or diplopia. We assessed the incidence and the etiology of visual symptoms in patients with intracranial germinoma tumors (ICGTs).

METHODS AND MATERIALS

We performed a blinded retrospective review of the clinical charts and the initial magnetic resonance imaging (MRI) of 28 patients with ICGT. Thirteen tumors were pineal, five suprasellar, seven bifocal, and further three involved either the optic nerve, the corpus callosum, or the brainstem.

RESULTS

Twelve patients reported visual disturbances, seven of whom mainly experienced a decrease in vision. Two of those were initially managed as "retrobulbar neuritis" when endocrinologic symptoms prompted assessment by MRI. Involvement of the optic pathway was underestimated, and both relapsed. Field deficits were definitive sequelae, whereas visual acuity was sometimes regressive in the absence of optic atrophy.

CONCLUSIONS

Compression or invasion of the optic pathway by germinomas is not a rare occurrence, and this possibility should not be overlooked when thickening or contrast enhancement is detected. Radiotherapy fields should be extended accordingly.

Primary intrinsic chiasmal germinoma

Intracranial germinomas are typically present in the suprasellar or pineal location, and their origin within the optic nerve or chiasm is extremely rare. We report a 25-year-old woman with an exophytic primary optic chiasm germinoma who underwent partial resection followed by radiation and had no detectable tumor on magnetic resonance imaging at 1-year follow-up.

Primary intrinsic optic chiasm germinoma

We report a 30-year-old woman with a primary intrinsic optic chiasm germinoma. The patient underwent a biopsy, and the pathology was determined to be a germinoma. Adjuvant radiation therapy was then carried out.